Position sensors of the type a spring is connected to a power source and the electrical resistance changes with the expansion and contraction of the spring, are well known in the art. In this art, the electrical resistance measured is a function of the relative positions of the spring and such sensors are often used in hydraulic cylinders to sense the related position of the end of the cylinder.
The sensors generally are a coil spring that is linearly compressible, but the sensor can be a helical rotatable spring.
In the use of sensors of this type, the spring is generally operated in a harsh environment which causes faulty readings or failure in a time period that is less than desirable.
The present invention is directed to overcome the problems of these heretofore utilized sensors and the sensor of this invention has the advantageous properties of being flexible and able to withstand repeated flexing, the coating has excellent adhesion to the spring, has good dielectric properties, has excellent thermal shock resistance, a low coefficient of friction, excellent solvent resistance, a wide temperature use range, and low temperature application to avoid effecting spring temper.